Cap assembly for a drug delivery device, kit for assembling a cap, method for assembling a cap and drug delivery device comprising a cap assembly

ABSTRACT

A multi-part cap assembly for a drug delivery device is provided, the cap assembly comprising: a first cap component, and a second cap component, wherein the first cap component is assembled to the second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented. Furthermore, a kit for assembling a cap and a method for assembling a cap are provided as well as a drug delivery device.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is the national stage entry of International Patent Application No. PCT/EP2018/055544, filed on Mar. 7, 2018, and claims priority to Application No. EP 17159522.6, filed on Mar. 7, 2017, the disclosures of which are incorporated herein by reference.

TECHNICAL FILED

The present disclosure relates to a cap or a cap assembly for a drug delivery device, particularly a multi-part cap or multi-part cap assembly, to a kit for assembling a cap, to a method for assembling a cap and to a drug delivery device comprising the cap or cap assembly.

BACKGROUND

Drug delivery devices which do comprise a cap with a plurality of parts are, for example, known from WO 2015/028439 A1.

SUMMARY

The present disclosure provides solutions which facilitate the provision of an improved cap assembly or cap and/or improve the production of the cap. It should be noted that, aside from the claimed subject matter, the present disclosure may also contain other advantageous configurations and elements such that the present disclosure shall not be regarded as being limited to the claimed subject matter.

An aspect of the present disclosure is directed to a cap or a cap assembly for a drug delivery device. Another aspect of the present disclosure is directed to a kit, which is expediently a kit for assembling a cap or cap assembly for a drug delivery device. Another aspect is directed to a method for assembling a cap or cap assembly for a drug delivery device. Yet another aspect is directed to a drug delivery device comprising the cap or cap assembly.

Accordingly, features disclosed in connection with one of these aspects are also considered as being disclosed for the other aspects. Likewise, features disclosed in conjunction with different embodiments may be combined with one another. The difference between the kit and the cap assembly or cap is that, in the kit, the components or parts of the cap have not been assembled yet, whereas the cap assembly or cap refers to a situation where the components or parts have been assembled already.

In an embodiment, the cap or cap assembly comprises a first cap component and a second cap component. The first cap component may be adjusted to provide an inner or interior surface of the cap. Particularly, the first cap component may be formed in a sleeve-like shape. The first cap component may be adjusted to receive a cartridge of the drug delivery device via a, preferably proximal, opening of the cap assembly or the first cap component. The length of the cap assembly may be greater than or equal to the length of a cartridge of the drug delivery device. The second cap component may be designed to form an outer or exterior surface of the cap. Particularly, the second cap component may be formed in a sleeve-like shape. The first cap component may be made of or comprise a plastic material. The second cap component may be made of or comprise a metal or a metal based alloy. Consequently, the outer appearance of the cap can be governed by the second cap component, which suggests a durable and stable cap of high value, whereas the interior may be formed by the first cap component, which can be designed to suit several functions easily, for example by way of injection moulding a plastic cap component, which enables the provision of several functional features like snap features or other features in the first cap component.

In an embodiment, the first cap component and the second cap component can be assembled to one another. The first cap component may, for example, be received in and/or secured relative to the second cap component. When assembling the cap assembly, the first cap component may be introduced into the second cap component, expediently via a proximal opening of the second cap component. When assembled, the first cap component and the second cap component may be secured to each other such that relative rotational and axial movement is prevented. The cap assembly comprising the two cap components may thus act as a single part.

In an embodiment, the first cap component and/or the second cap component comprises one or more openings, e.g. two openings. Preferably, the respective cap component has at least an opening at the proximal end, i.e. the proximal opening. If there are two openings, there is preferably one at the proximal end of the respective cap component and one at the distal end, i.e. the distal opening.

In the cap or cap assembly the first and second cap components are assembled to one another. The kit also comprises the first and second cap components as detailed above, but not yet assembled to one another, and, in the method, the first and second cap component as detailed above are provided for assembling the cap.

In an embodiment, one of the first cap component and the second cap component is provided with or comprises a guide track, preferably an axial guide track. The other one of the first cap component and the second cap component may be provided with or comprise a guide feature. The guide feature may be designed to cooperate with the guide track. The guide track and the guide feature may be arranged to cooperate to form a guiding interface, preferably an axial guiding interface, between the first cap component and the second cap component. Consequently, when the guide feature and the guide track cooperate, i.e. when the guiding interface is established, movement of the cap components relative to each other, expediently in the axial and/or the angular or rotational direction, is governed by the guiding interface. The axial guiding interface may be configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented. The axial guiding interface is expediently constructed such that relative axial movement, preferably only relative axial movement, between the first and second cap components is allowed. “Axial”, “radial”, “rotational”, and “angular” as used herein may be understood as being with respect to a main longitudinal axis of the cap/cap assembly or one or more components thereof such as the first or second cap component.

In an embodiment, the guiding interface is configured such that it restricts relative rotational movement to angles of equal to or less than one of the following values: 10°, 5°, 4°, 3°, 2° or 1°, 0.75°, 0.5°, 0.25°. Preferably, relative rotational movement is prevented entirely at least when the first and second cap components are fully assembled. By restricting or preventing the relative rotational movement between the cap components, it can be assured that, expediently already during the assembling process, a defined relative rotational orientation of the two cap components is achieved, which may have significant advantages. For example, features provided on one cap component do have a defined position relative to features on another cap component, which will simplify the assembling process and also increase the yield as cap components which have been assembled to each other in the wrong angular orientation might not be suitable for further use.

In an embodiment, the first cap component and/or the second cap component may be unitary. That is to say, the respective cap component may be formed as a single piece.

In an embodiment, the respective cap component may comprise a main body with the guide feature or the guide track being formed on the main body of the respective cap component.

In an embodiment, when assembling the multi-part cap assembly, the first cap component and the second cap component may be arranged with respect to each other such that the guiding interface is established. For doing so, the first cap component may be introduced into the second cap component. The guiding interface may be established, preferably only, after a first portion of relative movement, particularly relative axial movement, between the first cap component and the second cap component has been performed. In other words, before the guiding interface is established, there may be a situation where the guiding interface is not established, although the first cap component has already been received in the second cap component. After the guiding interface has been established, the first cap component and the second cap component may be moved relative to one another, particularly in the axial direction, towards an end position. This movement is expediently guided by the guiding interface, preferably from the onset of the guiding interface until the end position has been reached. In the end position, the first cap component and the second cap component may be secured to one another, expediently against relative axial and/or rotational movement.

In an embodiment, the cap, the first cap component and/or the second cap component do define a longitudinal axis, particularly a main longitudinal axis. The axes of the two cap components may coincide or be parallel.

In an embodiment, the guide track may extend in the axial direction. The guide track may be a straight track. The guide track may extend along the longitudinal axis, preferably parallel with respect to the axis. The guide track may coincide with the longitudinal axis when projected onto a plane comprising the axis. In other words, when seen in projection onto a plane which comprises the main longitudinal axis but does not comprise the guide track the guide track and the longitudinal axis may coincide.

In an embodiment, the first cap component and the second cap component are configured such that the relative angular orientations of the first cap component and the second cap component, in which the first cap component can be assembled to, e.g. arranged in the end position with respect to, the second cap component, are limited. This holds, preferably, even when disregarding the guiding interface mentioned above. Accordingly, aside from the guiding interface, the cap components may be designed such that they can be assembled to each other only in a limited number of relative angular orientations.

In an embodiment, the inner cross section of the second cap component and the outer cross section of the first cap component may be adjusted to one another at least in an adjusted region of the respective component. The adjustment may be performed by shaping the outer surface of the first cap component and the inner surface appropriately in the adjusted region of the respective cap component. When the cap components are misaligned, relative axial movement is not possible as the cross sectional shape does not permit this movement. When the cap components are aligned correctly, however, the adjusted sections of the cross section cooperate, e.g. they form a rotationally constrained interface or an interface of limited relative rotatability between the two components, and relative axial movement is possible.

Therefore, the first cap component and the second cap component can be pre-aligned, even if the guiding interface is not yet established. Consequently, the guide feature and the guide track may be pre-aligned such that they can be brought into mechanical cooperation for forming the guiding interface more easily and more reliably during the assembly of the cap assembly.

In an embodiment, the cap components are expediently designed such that a splined interface or pre-alignment interface is formed between the cap components while the two components are being assembled to one another and before the guiding interface is established by cooperation of the guide feature and the guide track.

In an embodiment, the relative angular orientations in which the first and second cap components can be assembled to one another are limited to a range of orientation angles, preferably a single and continuous range of orientation angles. Consequently, even when the axial guiding interface is not or not yet established, the cap components may be aligned in the range of orientation angles. The guiding interface is expediently configured to restrict the relative rotational movement which is permitted between the first cap component and the second cap component to a restricted range of angles. The restricted range of angles is expediently smaller, e.g. has a smaller extension, than the range of orientation angles. The restricted range of angles may be a subset of the range of orientation angles. The range of orientation angles is expediently such that the intended position in which the first and second cap components should be assembled is at 0° with deviations possible in both rotational directions up to to −α1 and +α2, respectively. α1 and α2 may be different or equal. By means of the pre-alignment, α1 and/or α2 may be already restricted to values equal to or less than one of the following values: 30°, 25°, 20°, 15°, 10°, 5°. The guiding interface may restrict the relative rotatability even more or prevent relative rotatability entirely. Consequently, by providing the guide track and the guide feature, a very defined relative rotational position may be assumed by the first and second cap components during the assembly and/or in the end position once the assembling process has been completed.

In an embodiment, the guiding interface is established in the end position. The guide track may comprise an axial end stop which cooperates with the guide feature to indicate when the end position has been reached.

In an embodiment, the guide track is a slot or a groove.

In an embodiment, the guide feature has one or more curved surfaces. The respective curved surface may be designed to interact with the guide track. A reliable guiding interface may be realized in this way. The respective surface may extend in the radial direction.

In an embodiment, the cap assembly comprises a third cap component. The third cap component may comprise or be provided with a third cap component fixing feature, e.g. a snap feature. The third cap component may be a clip element for the cap assembly. The clip element may be designed such that the cap can be clipped to a pocket or the like.

In an embodiment, the first cap component is provided with or comprises a first cap component fixing feature, e.g. a snap feature. The third cap component may be fixed to the first cap component by means of the first cap component fixing feature. The first cap component fixing feature is expediently designed and arranged to cooperate with the third cap component fixing feature provided on the third cap component in order to fix the third cap component to the first cap component.

In an embodiment, the second cap component is provided with or comprises a fixing guide track, in particular an axial or axially extending fixing guide track. The fixing guide track may be arranged to guide movement of the third cap component and/or the third cap component fixing means to or towards the first cap component fixing means. In other words, the second cap component may interact with the third cap component in order to guide a fixing feature of the third cap component to the first cap component fixing feature. As the guiding interface ensures a defined relative angular position between the second cap component and the first cap component it is also ensured that the third cap component fixing feature is reliably guided to the first cap component fixing feature and may cooperate with the first cap component fixing feature.

In an embodiment, the axial fixing guide track and the axial guide track extend in, are arranged in and/or are restricted to a common plane when the axial guiding interface is established. This plane may be a plane which also comprises the main longitudinal axis of the cap assembly or of components thereof.

In an embodiment, the third cap component is used to secure the first cap component and the second cap component with respect to one another, in particular with respect to relative axial movement. Consequently, when the first cap component fixing feature and the third cap component fixing feature cooperate, relative axial movement between the first cap component and the second cap component is prevented. Relative rotational movement may also be prevented by the third cap component and/or by the guiding interface, which may be still operative in the end position.

In an embodiment, the third cap component fixing feature and the first cap component fixing feature are arranged to cooperate, particularly only, when they are arranged in a fixing range of relative angular positions or orientations with respect to one another. Thus, even if they were at the correct relative axial position, i.e. corresponding axial locations, the fixing features could not cooperate if their relative angular position or orientation is arranged outside of the fixing range. Similar as above, 0° is the ideal relative angular position or orientation in which the fixing features should be arranged to allow cooperation. The tolerance which has to be met for still allowing proper cooperation of the fixing features may be as low as 1° or even less from the ideal position. Thus, the fixing range is very small. The fixing range may fully cover the relative angular positions or orientations in the restricted range of angles, when the guiding interface is established. The fixing range may not fully cover the relative angular positions orientations in the range of orientation angles. That is to say, the range of relative angular orientations which is possible when disregarding the guiding interface may comprise orientation angles where the fixing features of the first and third cap components could not cooperate. The guiding interface, however, restricts the range of possible relative angular positions or orientations to the restricted range of angles, where it is ensured that the fixing features can cooperate. In other words, a fixing range of angles may fully cover the restricted range of angles but not the range of orientation angles.

In an embodiment, the second cap component forms an outer surface of the cap assembly. The second cap component may be made of metal or of a metal alloy.

In an embodiment, the second cap component is a deep drawn component. Deep drawing facilitates the manufacturing of a metal or metal alloy second cap component. Deep drawing is a production method for metal components which is very cost effective, is suitable for high volumes, and/or ensures a high yield.

In an embodiment, the guide track is provided on the first cap component and the guide feature is provided on the second cap component or vice versa. Expediently, the guide feature is arranged on an inner surface of the second cap component and the guide track is arranged on an outer surface of the first cap component.

In an embodiment, the guide feature is formed by a protrusion. The protrusion may extend in the radial direction. The protrusion may be provided on an inner surface of the second cap component. The protrusion may be realised by deep drawing. The protrusion may protrude from a main body of the respective cap component. The protrusion may have a hemispherical shape.

In an embodiment, the second cap component, particularly an outer surface thereof, comprises a depression. The depression may have a hemispherical shape. The depression may be formed by a pressing operation that occurs as part of a multi-stage deep-drawing process. The protrusion may be defined by the depression. This facilitates manufacturing the protrusion in a deep drawing process as protrusion and depression can be formed simultaneously.

In an embodiment, the guide feature, particularly the protrusion, is defined by a depression. The guide feature may be arranged on the opposite surface of the same cap component which comprises the depression. The depression may be the same depression as discussed further above.

In an embodiment, a section of the third cap component, particularly a radially extending section of the third cap component, which protrudes radially from the remainder of the third cap component, may be arranged in the depression. Consequently, the depression may provide for a bearing surface of a clip element of the cap assembly.

In an embodiment, the third cap component or clip element is a multi-part component. The third cap component may comprise a first or inner part, preferably a plastic part, which is connected with a second or outer part, e.g. an outer shell, preferably of metal or a metal alloy.

In an embodiment, the guide track comprises a lead-in region, preferably at the start of the guide track. Via a transition region of the guide track, the lead-in region may pass into a guiding region. In the lead-in region, the relative orientation angles, in which the guide feature can cooperate with the guide track may be wider than in the guiding region. In other words, the lead-in region may be arranged to accept the guide feature and guide the guide feature to a guiding region of the guide track, in which the guide feature is guided more tightly than in the lead-in region. This ensures a tight guiding when the guiding interface is established, which is expediently the case when the guide feature and the guiding region cooperate. Consequently, even if the first and second cap components are misorientated or misaligned with respect to one another in the angular direction such that the guide feature could, without the lead-in region, not cooperate with the guide track, the lead-in region can capture the guide feature during relative axial movement of the cap components during the assembling process and orient the first and second cap components appropriately in the angular direction such that the guide feature and the guiding region of the guide track can cooperate.

In an embodiment, the drug delivery device, which comprises the cap assembly, comprises a cartridge containing a drug, preferably a plurality of doses of the drug, which is preferably a fluid drug. The drug delivery device is expediently configured such that the cartridge is replaceable. In other words, the drug delivery device is preferably reusable. The device may be a pen-type device.

In a preferred embodiment, a multi-part cap assembly for a drug delivery device comprises a first cap component and a second cap component, wherein the first cap component is assembled to, in particular received in and/or secured relative to, the second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented.

In a further preferred embodiment, a kit for assembling a multi-part cap for a drug delivery device comprises a first cap component and a second cap component which can be assembled for the cap assembly, wherein the first cap component can be received in and secured relative to the second cap component, and wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented.

In a further preferred embodiment, a method for assembling a multi-part cap for a drug delivery device comprises the steps of:

providing a first cap component,

providing a second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented,

introducing the first cap component into the second cap component such that the axial guiding interface is established, moving the first cap component and the second cap component relative to one another in the axial direction towards an end position, this movement being guided by the axial guiding interface, and

securing the first cap component and the second cap component to one another in the end position.

The preferred embodiments discussed above do have particular advantages which become apparent from the description further above and the following description.

Features which are described herein above and below in conjunction with different aspects or embodiments, may also apply for other aspects and embodiments. Further features and advantageous embodiments of the present disclosure will become apparent from the following description of the exemplary embodiments in conjunction with the figures, in which:

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a drug delivery device with a cap attached in accordance with an embodiment;

FIG. 2 shows the drug delivery device of FIG. 1 with the cap removed and a dose of 79 units dialed;

FIG. 3 shows in an exploded view the components of the drug delivery device of FIG. 1;

FIG. 4 shows the outer body of the drug delivery device of FIG. 1;

FIG. 5a shows the inner body of the drug delivery device of FIG. 1;

FIG. 5b shows a detail of the inner body of FIG. 5 a;

FIG. 6 shows the cartridge holder of the drug delivery device of FIG. 1;

FIG. 7a shows a first display member component of the drug delivery device of FIG. 1;

FIG. 7b shows a detail of the first display member of FIG. 7 a;

FIG. 8 shows a second display member component of the drug delivery device of FIG. 1;

FIG. 9 shows a first driver component of the drug delivery device of FIG. 1;

FIG. 10 shows a second driver component of the drug delivery device of FIG. 1;

FIG. 11 shows a third driver component of the drug delivery device of FIG. 1;

FIG. 12 shows the last dose nut of the drug delivery device of FIG. 1;

FIG. 13 shows a clutch component of the drug delivery device of FIG. 1;

FIG. 14 shows a first clicker component of the drug delivery device of FIG. 1;

FIG. 15 shows a second clicker component of the drug delivery device of FIG. 1;

FIG. 16 shows the button of the drug delivery device of FIG. 1;

FIG. 17 shows a cut-away view of the proximal part of the drug delivery device of FIG. 1 in a zero unit position with the button released;

FIG. 18 shows a cut-away view of the proximal part of the drug delivery device of FIG. 1 in a position with some units dialed; and

FIG. 19 shows a cut-away view of the proximal part of the drug delivery device of FIG. 1 in a zero unit position with the button pressed.

FIG. 20 shows an exploded view of a cap assembly;

FIG. 21 shows a sectional view of a proximal region of an outer cap element;

FIG. 22 shows a three-dimensional cut out view of the outer cap element;

FIG. 23 shows a sectional view of the proximal section of the cap during attachment;

FIG. 24 shows a sectional view of the proximal section of the cap after attachment;

FIG. 25 shows a sectional view of the proximal section of an alternative embodiment of the cap after attachment;

FIG. 26 shows a perspective view of a first component of a clip element;

FIG. 27 shows a perspective view of an outer component;

FIG. 28 shows a perspective view of an inner component;

FIG. 29 shows a schematic cross-sectional view of parts of a cap assembly;

FIG. 30 shows a portion of the cap assembly in a longitudinal section;

FIG. 31 shows a perspective view of a first component of a clip element;

FIG. 32 shows a perspective view of a cap assembly;

FIG. 33 shows a sectional view of the cap assembly of FIG. 32;

FIG. 34 shows a distal portion of a clip element;

FIG. 35 shows a sectional view of a component of a clip element;

FIG. 36 shows a sectional view of a clip element;

FIG. 37 shows a sectional view of a clip element;

FIG. 38 shows another sectional view of the clip element of FIG. 37;

FIG. 39 shows a portion of the clip element of FIG. 38.

FIG. 40 shows parts of an embodiment of a cap assembly in an unassembled state.

FIG. 41 shows the cap assembly with the parts shown in FIG. 40 in an assembled state.

FIG. 42 shows a state during the assembling of the cap assembly of FIG. 41 on the basis of a partial sectional view in FIG. 42A and a perspective view in FIG. 42B.

FIG. 43 shows a side view of the cap assembly.

Like elements, elements of the same kind and identically acting elements may be provided with the same reference numerals in the figures. Additionally, the figures may be not true to scale. Rather, certain features may be depicted in an exaggerated fashion for better illustration of important principles.

DETAILED DESCRIPTION

FIGS. 1 and 2 show a drug delivery device 1 in the form of an injection pen. Consequently, references herein using the wording “an injection pen” or similar wordings should also be understood as relating to a drug delivery device, preferably a pen-type drug delivery device. The device 1 has a distal end (lower end in FIG. 1) and a proximal end (upper end in FIG. 1). The components of the drug delivery device 1 are shown in FIG. 3 in more detail. The drug delivery device 1 comprises an outer housing part 10, an inner body 20, a piston rod 30, a driver 40, a nut 50, a display member 60, a button 70, a cartridge holder 80 for receiving a cartridge 81, a clutch 90, a clicker 100, a spring 110, a cap 120 and a window insert 230. A needle arrangement (not shown) comprising a needle hub and a needle cover may be provided as additional components, which can be exchanged. The piston rod 30 comprises a bearing 31. The driver 40 comprises a distal driver part 41, a proximal driver part 42 and a coupler 43. The display member 60 comprises a number sleeve 61 and a dial sleeve 62. The clicker 100 comprises a distal clicker part 101, a proximal clicker part 102 and a spring 103.

The outer housing part 10, which is shown in FIG. 4, is a generally tubular element having a distal part 11 for attaching the inner body 20 and a proximal part, which is provided with a rotational hard stop 12 on its inner surface (not shown) which contact mating faces of the display member 60 when the maximum units (in this example 80 U) stop is engaged. The end face also serves as the end of dose dispense stop for the button 70, and the bore in the end face centers the display member 60 during both dialing and dispense. An aperture 13 is provided for receiving window insert 230. The outer body 10 provides the user with a surface to grip and react against during dispense.

The inner body 20 is a generally tubular element having different diameter regions. As can be seen in FIGS. 17 to 19, the inner body 20 is received in the outer body 10 and permanently fixed therein to prevent any relative movement of the inner body 20 with respect to the outer body 10. The inner body has the functions to house the drive mechanism within, guiding the clickers and the last dose nut 50 via internal splines, to provide an internal thread through which the piston rod 30 (lead screw) is driven, to support and guide the number sleeve 61 and the dial sleeve 62 on an external thread form, to secure the cartridge holder 80 and to secure the outer body 10 and the window insert 230.

The outermost diameter of the inner body 20 also forms part of the visual design and remains visible when the cap 120 is secured to the cartridge holder 80 as a ring separating the cap 120 from the outer body 10. This visible ring also has depressions which align with the cap snap features on the cartridge holder 80 to indicate that the cartridge holder has been correctly fitted.

An external thread 21 is provided on the outer surface of the inner body 20. Further, splines 22 (FIG. 5b ) are provided on the inner surface of the inner body 20. These internal splines 22 guide the clicker 100 axially during both dialing and dispense and also prevent the last dose nut 50 from rotating. Some of the splines may be wider to ensure correct rotational assembly of the internal components, and these wider splines may have a stepped entry and angled surface to encourage the last dose nut 50 to rotate up against the stop face on the distal drive sleeve 41 during assembly. At the open end shown in FIG. 5b there are additional short splines which together with the alternating long splines 22 are used to rotationally lock the button 70 (dose dial grip) at the end of dispense and serve to increase the strength of the 0 U dial stop when the button 70 is depressed. This is achieved by engagement with male spline features on the clutch component 90.

Bayonet features 23 guide the cartridge holder 80 into the mechanism during cartridge replacement, compressing the cartridge bias spring 110, and then back off the cartridge holder 80 a small distance in order to reduce axial play in the mechanism. Snap features inside the inner body 20 lock the cartridge holder 80 rotationally when it has been correctly fitted. The profile of these snaps aims to prevent the user from partially fitting the cartridge holder 80, the cartridge bias spring 110 ejecting the cartridge holder 80 if the snaps have not at least started to engage. A window retention nose 24 retains the window insert 230 when the outer body 10 and window insert 230 assembly is axially inserted onto the inner body 20. Two diametrically opposite stop faces 25 define the rotational end position for the number sleeve 61. This end position is the end of dose detent position for the minimum dose (0 U).

The piston rod 30 is an elongate element having two external threads 32, 33 with opposite hand which overlap each other. One of these threads 32 engages the inner thread of the inner body 20. A disk-like bearing 31 is provided at the distal end of the piston rod 30. The bearing 31 may be a separate component as shown in FIG. 3 or may be attached to the piston rod 30 as a one-piece component via a predetermined breaking point.

The piston rod 30 transfers the dispense load from the driver 40 to the bearing 31, creating a mechanical advantage greater than 1:1 by converting the torque generated on the piston rod 30 by the driver 40 thread interface into additional axial load as the piston rod passes through the thread in the inner body 20. The piston rod 30 is reset by pressing on the bearing 31 and this in turn rotates the piston rod back into the inner body 20. This disengages and then rotates the distal drive sleeve 41, resetting the last dose nut 50 back to its starting position on the distal drive sleeve 41.

The driver 40 is a generally tubular element having in the embodiment shown in the Figures three components which are depicted in FIGS. 9 to 11 in more detail.

The distal drive sleeve 41 engages with the piston rod thread 33 to drive the piston rod 30 through the inner body 20 during dose delivery. The distal drive sleeve 41 is also permanently connected to the coupler 43 which in turn is releasably engaged through reset clutch features to the proximal drive sleeve 42. The two halves of the drive sleeve are rotationally and axially connected during dialing and dispense, but are de-coupled rotationally during device reset so that they can rotate relative to each other.

The external thread 44 engages with the last dose nut 50. The thread form has three stages, a shallow first stage (left hand side in FIG. 9) over which the nut 50 travels to count the majority of the units dialed, a fast stage over which the last dose nut moves rapidly axially prior to engaging the stop faces, and a final shallow section which ensures that when the stop faces have engaged, the axial restraint on the nut 50 extends over a reasonable length of thread form. Four equi-spaced stop faces 45 engage with mating stop faces 51 on the last dose nut 50 to limit the number of units that can be dialed. Splines 46 are provided at the proximal end of distal drive sleeve 41 to transfer torque from or to the coupler 43, which may be snapped on the distal drive sleeve 41.

The proximal drive sleeve 42 shown in FIG. 10 supports the clicker components 100 and the clutch 90 and transfers rotational movement from the dose button 90 to the coupler 42 and distal drive sleeve 41.

Teeth features 47 located at the distal end of proximal drive sleeve 42 engage with the reset clutch features on the coupler 43 to connect both halves of the drive sleeve during dialing and dispense. During reset these teeth 47 disengage.

Several splines are provided on the outer surface of proximal drive sleeve 42 engaging with the distal and/or proximal clicker part 101,102, preventing relative rotation during dialing and dispense. Further splines, which are located in the middle region of proximal drive sleeve 42, engage with the clutch 90 component. They may be arranged to be rotationally non-symmetric so that the various clicker components cannot be assembled accidentally upside down.

The proximal portion of proximal drive sleeve 42 has four arms or fingers 48. A hook-like bearing surface 49 exists on the underside (as seen in FIG. 10) of flange segments on the end of the flexible fingers 48. The flexible fingers 48 are separated with gaps or slots that make space for the button 70 to snap to the clutch 90 and also enable these fingers to flex inwards during assembly of the proximal drive sleeve 42 to the dial sleeve 62. After assembly the hooks 49 retain the proximal drive sleeve 42 relative to the dial sleeve 62 under the reaction force from the spring 103. During dispense the button 70 depresses the spring 103 via the clutch 90 and the clicker components and this spring 103 is reacted through the coupler 43 to the proximal drive sleeve 42 which then through these bearing surfaces applies axial load to the dial sleeve 62. This axial load drives the dial sleeve 62 and hence number sleeve 61 along the helical thread of the inner body 20, back into the body of the device, until the 0 U stop faces on the number sleeve 61 contact the inner body 20.

The coupler 43 shown in FIG. 11 rotationally couples the two halves of the drive sleeve together during dialing and dispense, whilst allowing them to de-couple during reset. The coupler 43 has to also transfer the last dose protection stop load from the proximal drive sleeve 42 to the distal drive sleeve 41. Two sets of teeth are provided in the coupler 43 for engaging teeth 46 and teeth 47, respectively. The coupler 43 is snapped onto distal drive sleeve 41 allowing limited relative axial movement with respect to the proximal drive sleeve 42.

The nut 50 is provided between the inner body 20 and the distal drive sleeve 41 of driver 40. Stop faces 51 are located on the proximal face of last dose nut 50 to limit the number of units that can be dialed if the stop faces 51 contact stops 45 of distal drive sleeve 41. The function of the last dose nut 50 is to prevent the user from dialing beyond a finite amount. This limit is based on the dispensable volume of the cartridge 81 and when reached, the user must replace the cartridge 81 and reset the device.

External ribs 52 of the nut 50 engage splines 22 of inner body 20. An internal thread 53 of the nut engages the external thread 44 of distal drive sleeve 41. As an alternative, splines and ribs could be provided on the interface between the nut 50 and the driver 40 and threads could be provided on the interface between the nut 50 and the inner body 20. As a further alternative, the nut 50 may be designed as e.g. a half nut.

The display member 60 is a generally tubular element which is composed of number sleeve 61 and dial sleeve 62 which are snapped together during assembly to axially and rotationally constrain these two components, which thus act as a single part.

The main functions of the number sleeve 61 depicted in FIG. 8 are to provide a surface onto which dose numbers can be printed to display the dialed dose, to guide the helical path of the internal mechanism during dialing to follow the helical thread form on the piston rod 30 when threaded to the inner body 20 and to attach to the dial sleeve 62.

The number sleeve 61 is designed to be fully enclosed in the outer body 10 during dialing and dispense and therefore only the dialed dose is visible to the user through the window aperture. The number sleeve has a 0 U (minimum dose) stop face 63 to limit its travel when dialed in but the 80 U (maximum dose) stop faces that limit the dialed out condition are located on the dial sleeve 62. At the end of each dispense stroke, this stop face 63 engages with mating surface 25 on the inner body 20 to limit the rotational position of the number sleeve 61.

A helical drive face 64 forms a thread that guides the number sleeve 61 during dialing and dispense to follow the helical path 21 on the inner body.

The dial sleeve 62 is assembled to the number sleeve 61 such that once assembled, no relative movement is allowed. The parts are made as separate components to enable both molding and assembly. Also, whereas the number sleeve 61 is preferably white to give contrast for the e.g. black dose numbers, the dial sleeve 62 color can be chosen to suit the aesthetics or perhaps to distinguish the drug type.

At the proximal end, the dial sleeve 62 has internal clutch features 65 that engage with the clutch component 90 during dialing and disengage from the clutch during dispense. These clutch features 65 rotationally lock the dial sleeve 62 to the clutch 90 during dialing and when the 0 U and 80 U stops are engaged. When the button 70 is depressed these clutch features disengage to allow the clutch 90 and drive mechanism to move axially whilst the dial sleeve 62 and number sleeve 61 spin back to the 0 U start position.

The dial sleeve 62 rotates out during dialing through its engagement with the clutch 90 and number sleeve 61, and rotates back in during dispense under the axial force applied by the proximal drive sleeve 42 to a flange-like bearing face 66 on the end of the dial sleeve. This bearing face 66 engages with the flexible arms 48 of the proximal drive sleeve 42 during dispense. Two diametrically opposite faces 67 engage with the outer body 10 when the maximum dose (e.g. 80 U) has been dialed, forming the maximum dose stop faces.

A ratchet arm 68 engages with ratchet features on the button 70 (dose dial grip) to provide audible feedback during dispense, giving one click per unit delivered. Further, this prevents the user from gripping and rotating the number sleeve 61 outwards from a partially dialed out position whilst holding the button 70 pressed in. This would back wind the piston rod 30 which would result in an under dose on the subsequent dialed dose. It may further strengthen the 0 U stop.

The button 70 which is shown in FIG. 16 serves as a dose dial grip and is retained by the clutch 90 to transfer the actions of the user to the clutch. It also carries ratchet teeth 71 that engage the ratchet arm 68 on the dial sleeve 62, which serves as the dispensing clicker giving audible feedback (ratchet clicks), and an end face 72 which serves as the dose completion stop face with the outer body 10. This end face 72 thus serves to define the end position during dispense when it contacts the outer body 10 to provide a very positive stop improving dose accuracy.

A central sleeve-like portion of button 70 is provided with four arms 73 having hook-like snap features 74 at their respective distal ends. The arms 73 form splined surfaces engaging with the clutch 90 to transfer torque from the button 70 through the clutch to the dial sleeve 62 and proximal drive sleeve 42. The snap features 74 engage apertures in the clutch 90 and are designed with angled undercut faces to maintain engagement when an axial load is applied to pull the button 70 out of the pen body 10. The space between arms 73 defines pockets giving clearance for the flexible arms 48 of proximal drive sleeve 42 to slide freely relative to the button 70 and clutch 90 when the button 70 is depressed and released during dose dispense.

The cartridge holder 80 attaches to the inner body 20 with a bayonet connection 82 and houses the glass ampoule or cartridge 81 containing the medication to be dispensed. The cartridge holder 80 includes an aperture 83 in the rear face (as seen in FIG. 6) which if gripped by the user prevents the ampoule from falling out when the cartridge holder is removed from the inner body 20. The front face is printed with a dose number scale. The threaded distal end 84 is used to attach disposable pen needles.

The term “drug” or “medication”, as used herein, preferably means a pharmaceutical formulation containing at least one pharmaceutically active compound, wherein in one embodiment the pharmaceutically active compound has a molecular weight up to 1500 Da and/or is a peptide, a proteine, a polysaccharide, a vaccine, a DNA, a RNA, an enzyme, an antibody or a fragment thereof, a hormone or an oligonucleotide, or a mixture of the above-mentioned pharmaceutically active compound,

wherein in a further embodiment the pharmaceutically active compound is useful for the treatment and/or prophylaxis of diabetes mellitus or complications associated with diabetes mellitus such as diabetic retinopathy, thromboembolism disorders such as deep vein or pulmonary thromboembolism, acute coronary syndrome (ACS), angina, myocardial infarction, cancer, macular degeneration, inflammation, hay fever, atherosclerosis and/or rheumatoid arthritis,

wherein in a further embodiment the pharmaceutically active compound comprises at least one peptide for the treatment and/or prophylaxis of diabetes mellitus or complications associated with diabetes mellitus such as diabetic retinopathy,

wherein in a further embodiment the pharmaceutically active compound comprises at least one human insulin or a human insulin analogue or derivative, glucagon-like peptide (GLP-1) or an analogue or derivative thereof, or exendin-3 or exendin-4 or an analogue or derivative of exendin-3 or exendin-4.

Insulin analogues are for example Gly(A21), Arg(B31), Arg(B32) human insulin; Lys(B3), Glu(B29) human insulin; Lys(B28), Pro(B29) human insulin; Asp(B28) human insulin; human insulin, wherein proline in position B28 is replaced by Asp, Lys, Leu, Val or Ala and wherein in position B29 Lys may be replaced by Pro; Ala(B26) human insulin; Des(B28-B30) human insulin; Des(B27) human insulin and Des(B30) human insulin.

Insulin derivates are for example B29-N-myristoyl-des(B30) human insulin; B29-N-palmitoyl-des(B30) human insulin; B29-N-myristoyl human insulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29 human insulin; B28-N-palmitoyl-LysB28ProB29 human insulin; B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N-palmitoyl- ThrB29LysB30 human insulin; B29-N-(N-palmitoyl-Y-glutamyl)-des(B30) human insulin; B29-N-(N-lithocholyl-Y-glutamyl)-des(B30) human insulin; B29-N-(ω-carboxyheptadecanoyl)-des(B30) human insulin and B29-N-(ω-carboxyheptadecanoyl) human insulin.

Exendin-4 for example means Exendin-4(1-39), a peptide of the sequence H-His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2.

Exendin-4 derivatives are for example selected from the following list of compounds:

H-(Lys)4-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

H-(Lys)5-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

des Pro36 Exendin-4(1-39),

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [TrpO2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39); or

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39),

wherein the group -Lys6-NH2 may be bound to the C-terminus of the Exendin-4 derivative;

or an Exendin-4 derivative of the sequence

des Pro36 Exendin-4(1-39)-Lys6-NH2 (AVE0010),

H-(Lys)6-des Pro36 [Asp28] Exendin-4(1-39)-Lys6-NH2,

des Asp28 Pro36, Pro37, Pro38Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Trp(O2)25] Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Met(O)14, Asp28] Exendin-4(1-39)-Lys6-NH2,

des Met(O)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1-39)-NH2,

H-(Lys)6-desPro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Lys6-des Pro36 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25] Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(S1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2;

or a pharmaceutically acceptable salt or solvate of any one of the afore-mentioned Exendin-4 derivative.

Hormones are for example hypophysis hormones or hypothalamus hormones or regulatory active peptides and their antagonists as listed in Rote Liste, ed. 2008, Chapter 50, such as Gonadotropine (Follitropin, Lutropin, Choriongonadotropin, Menotropin), Somatropine (Somatropin), Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin, Buserelin, Nafarelin, Goserelin.

A polysaccharide is for example a glucosaminoglycane, a hyaluronic acid, a heparin, a low molecular weight heparin or an ultra low molecular weight heparin or a derivative thereof, or a sulphated, e.g. a poly-sulphated form of the above-mentioned polysaccharides, and/or a pharmaceutically acceptable salt thereof. An example of a pharmaceutically acceptable salt of a poly-sulphated low molecular weight heparin is enoxaparin sodium.

Antibodies are globular plasma proteins (˜150 kDa) that are also known as immunoglobulins which share a basic structure. As they have sugar chains added to amino acid residues, they are glycoproteins. The basic functional unit of each antibody is an immunoglobulin (Ig) monomer (containing only one Ig unit); secreted antibodies can also be dimeric with two Ig units as with IgA, tetrameric with four Ig units like teleost fish IgM, or pentameric with five Ig units, like mammalian IgM.

The Ig monomer is a “Y”-shaped molecule that consists of four polypeptide chains; two identical heavy chains and two identical light chains connected by disulfide bonds between cysteine residues. Each heavy chain is about 440 amino acids long; each light chain is about 220 amino acids long. Heavy and light chains each contain intrachain disulfide bonds which stabilize their folding. Each chain is composed of structural domains called Ig domains. These domains contain about 70-110 amino acids and are classified into different categories (for example, variable or V, and constant or C) according to their size and function. They have a characteristic immunoglobulin fold in which two β sheets create a “sandwich” shape, held together by interactions between conserved cysteines and other charged amino acids.

There are five types of mammalian Ig heavy chain denoted by α, δ, ε, γ, and μ. The type of heavy chain present defines the isotype of antibody; these chains are found in IgA, IgD, IgE, IgG, and IgM antibodies, respectively.

Distinct heavy chains differ in size and composition; α and γ contain approximately 450 amino acids and δ approximately 500 amino acids, while μ and ε have approximately 550 amino acids. Each heavy chain has two regions, the constant region (C_(H)) and the variable region (V_(H)). In one species, the constant region is essentially identical in all antibodies of the same isotype, but differs in antibodies of different isotypes. Heavy chains γ, α and δ have a constant region composed of three tandem Ig domains, and a hinge region for added flexibility; heavy chains μ and ε have a constant region composed of four immunoglobulin domains. The variable region of the heavy chain differs in antibodies produced by different B cells, but is the same for all antibodies produced by a single B cell or B cell clone. The variable region of each heavy chain is approximately 110 amino acids long and is composed of a single Ig domain.

In mammals, there are two types of immunoglobulin light chain denoted by λ and κ. A light chain has two successive domains: one constant domain (CL) and one variable domain (VL). The approximate length of a light chain is 211 to 217 amino acids. Each antibody contains two light chains that are always identical; only one type of light chain, κ or λ, is present per antibody in mammals.

Although the general structure of all antibodies is very similar, the unique property of a given antibody is determined by the variable (V) regions, as detailed above. More specifically, variable loops, three each the light (VL) and three on the heavy (VH) chain, are responsible for binding to the antigen, i.e. for its antigen specificity. These loops are referred to as the Complementarity Determining Regions (CDRs). Because CDRs from both VH and VL domains contribute to the antigen-binding site, it is the combination of the heavy and the light chains, and not either alone, that determines the final antigen specificity.

An “antibody fragment” contains at least one antigen binding fragment as defined above, and exhibits essentially the same function and specificity as the complete antibody of which the fragment is derived from. Limited proteolytic digestion with papain cleaves the Ig prototype into three fragments. Two identical amino terminal fragments, each containing one entire L chain and about half an H chain, are the antigen binding fragments (Fab). The third fragment, similar in size but containing the carboxyl terminal half of both heavy chains with their interchain disulfide bond, is the crystalizable fragment (Fc). The Fc contains carbohydrates, complement-binding, and FcR-binding sites. Limited pepsin digestion yields a single F(ab′)2 fragment containing both Fab pieces and the hinge region, including the H-H interchain disulfide bond. F(ab′)2 is divalent for antigen binding. The disulfide bond of F(ab′)2 may be cleaved in order to obtain Fab′. Moreover, the variable regions of the heavy and light chains can be fused together to form a single chain variable fragment (scFv).

Pharmaceutically acceptable salts are for example acid addition salts and basic salts. Acid addition salts are e.g. HCl or HBr salts. Basic salts are e.g. salts having a cation selected from alkali or alkaline, e.g. Na+, or K+, or Ca2+, or an ammonium ion N+(R1)(R2)(R3)(R4), wherein R1 to R4 independently of each other mean: hydrogen, an optionally substituted C1-C6-alkyl group, an optionally substituted C2-C6-alkenyl group, an optionally substituted C6-C10-aryl group, or an optionally substituted C6-C10-heteroaryl group. Further examples of pharmaceutically acceptable salts are described in “Remington's Pharmaceutical Sciences” 17. ed. Alfonso R. Gennaro (Ed.), Mark Publishing Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia of Pharmaceutical Technology.

Pharmaceutically acceptable solvates are for example hydrates.

A tubular clutch 90 is provided between the display member 60 and the button 70. The clutch is fixed relative to and retains the button 70 and together they travel axially relative to the proximal drive sleeve 42 when the button 70 is depressed during dispense, disengaging the clutch teeth from the dial sleeve 62. It also transfers torque from the button to the proximal drive sleeve 42, and the dialing and 0 U/80 U stop loads from the button via the clutch teeth to the dial sleeve and number sleeve.

Drive sleeve splines 91 provided on an inner surface of the clutch engage with the proximal drive sleeve 42. At the distal end face, clutch biasing teeth 92 are provided which mate with similar teeth on the proximal clicker part 102 to ensure that in the button out position (dialed dose) the clutch is locked in rotation to the proximal clicker part 102 under the biasing action of the clutch spring 103. The teeth 92 are shallow in height to prevent the proximal clicker part 102 from engaging with splines on the proximal drive sleeve 42 during dialing. Four snap apertures 93 serve to retain the snap features 74 of button 70. Near its proximal end, the clutch has splines 94 which at the end of dispense with the button 70 depressed lock to the inner body 20 to prevent the user from rotating the button 70 below the 0 U position.

Clutch teeth 95 engage with clutch teeth 65 of the dial sleeve to rotationally couple the button 70 via the clutch to the number sleeve 61. During dispense the clutch is moved axially so as to disengage these clutch teeth 95 releasing the dial sleeve 62 to rotate back into the device whilst the clutch 90 and hence driver 40 move axially to dispense the dose.

The clicker 100 comprises a distal clicker part 101, a proximal clicker part 102 and a spring 103. The clutch spring 103 serves to bias the button 70 out so that at the end of a dose the button 70 pops out, re-engaging the clutch 90 with the dial sleeve 62 ready for dialing. Further, it provides the spring force for the clicker components to act as clickers and also as detent positions for the number sleeve 61. In addition, it holds the two halves of the drive sleeves 41, 42 in rotational engagement during dialing and dispense, whilst allowing them to disengage during device reset.

The distal clicker part 101 is permanently splined to the proximal drive sleeve 42 and engages with the proximal clicker part 102 which in turn is splined to the inner body 20. During dialing when the drive sleeve is rotated relative to the inner body, the two clickers 101, 102, rotate relative to each other under the compression force of the clutch spring 103. This force combined with the clicker teeth formed on the end face of each clicker provides the clicks and also the detent dialing positions.

During dispense the two clickers 101, 102 are pressed together under the dispense load and therefore prevent relative rotation between the proximal drive sleeve 42 and inner body 20, driving the piston rod forwards to deliver the dose. The splines 104 on the inner bore rotationally couple the distal clicker part 101 to the proximal drive sleeve 42 at all times, but allow free axial movement when the button 70 is depressed during dispense and when the two clickers ride over each other during dialing. The profile of the clicker teeth 105, 106 on both distal clicker part 101 and proximal clicker part 102 are identical and ride over each other under the compressive load from the spring 103 during dialing.

The proximal clicker part 102 is permanently splined to the inner body 20 by external splines 107 which prevent relative rotation with the inner body during both dialing and dispense, providing clicks during dialing and locking the proximal drive sleeve 42 in rotation during dispense. Additional cylindrically shaped splines 108 also couple the proximal clicker part 102 rotationally to the proximal drive sleeve 42 when the button 70 is depressed, this preventing the user from dialing past 80 units with the button depressed. Proximal clicker part 102, in addition to the primary clicker teeth 106, has clutch biasing teeth 109 on the opposite end face. These teeth mate with similar teeth 92 on the clutch to ensure that in the button out position (dialed dose) the clutch is locked in rotation to the proximal clicker part 102 under the biasing action of clutch spring 103.

The cartridge bias spring 110 is assembled as two components one after the other, the lower first and the upper second. The spring combination serves to apply an end load to the cartridge 81 at extremes of tolerance so as to bias it forwards onto the end face of the ferrule in the cartridge holder 80. This ensures that when the user removes and attaches a needle, the friction between the needle cannula and septum of the cartridge does not move the cartridge 81 axially relative to the cartridge holder 80. The bias spring 110 also acts to provide a force against which the user has to connect the cartridge holder 80 and this may add to the tactile feedback of this bayonet joint. The spring 100 also serves to eject the cartridge holder 80 if the cartridge holder is not rotated into a secure position, highlighting this error to the user.

The cap 120 serves to protect the cartridge holder 80 from damage and the cartridge 81 itself from dust dirt ingress on to the area around the septum. The cap 120 is designed to accommodate a standard pen injector needle. The cap 120 comprises a clip element 134 or fixing element for attaching the cap 120 and, hence, the drug delivery device 1 to a further element, e.g. a jacket pocket of the user. Preferably, the clip element 134 is snap-fitted to the cap 120. Details concerning the structure of the cap 120 and the clip element 134 as well as their connection are described later on.

The window insert 230 may include a lens to magnify the dose numbers e.g. by approximately 25% from their printed size. The window insert 230 may be back printed to protect the printed surface from abrasion and also to maximize the light entering through the window aperture, giving uniform illumination of the dose numbers and white area around these numbers. Arrows may be printed adjacent to the window aperture that indicate the dose dialed.

In the following, the function of the drug delivery device and its components will be explained in more detail with reference to FIGS. 17 to 19.

To use the device, a user has to select a dose. In the start (at rest) condition as shown in FIG. 17 the display member 60 indicates the number of doses dialed to the user. The number of dialed units can be viewed through the dose window 230 in the outer body 10. Due to the threaded engagement between the display member 60 and the inner body 20 rotation of the button 70 in a clockwise fashion causes the display member 60 to wind out of the device and incrementally count the number of units to be delivered. FIG. 18 shows an intermediate stage of dialing (e.g. 7 of 80 units).

During dose setting button 70, driver 40 and display member 60 are rotationally locked together via clutch 90. Further, button 70, driver 40 and display member 60 are axially coupled. Thus, these three components wind out of the outer housing 10 during dose setting. Clockwise rotation of the button 70 causes the driver 40 to rotate and in doing so it advances along the piston rod 30 which remains fixed throughout dialing. The clicker arrangement 100 provides tactile and audible feedback to the user when dialing doses. At the maximum settable dose of 80 units, the stop features 12 and 67 engage to prevent further dialing.

The last dose nut 50 provides the function of counting the number of dispensed units. The nut 50 locks the device at the end of cartridge life and as such no more drug can be dialed by the user. The last dose nut 50 and the driver 40 are connected via a threaded interface as explained above. Further, the last dose nut 50 is assembled into splines 22 such that the nut 50 and the inner body 20 are rotationally locked together (at all times). Rotation of the driver 40 during dialing causes the nut 50 to advance along the thread 44. The nut 50 is free to slide axially within the inner body 20 at all times which allows advancement of the nut. The change in pitch of thread 44 shown in FIG. 9 towards the final doses axially accelerates the advancement of the nut 50 towards the end of cartridge life lockout condition. At the end of life condition, the stop features 51 of the last dose nut 50 contact the corresponding features 45 on the driver 40. The splined contact with inner body 20 reacts any torque transmitted by these stop features 45.

With the desired dose dialed, the device 1 is ready for dose dispensing. This basically requires pushing button 70 which will result in a disengagement of the clutch 90 from dial sleeve 62 thus allowing relative rotation between the display member 60 and the button 70. In all conditions the driver 40 and the button 70 are rotationally locked together by engagement of arms 73 and fingers 48 and by splines 91 engaging corresponding splines on proximal drive sleeve 42. Thus, with the clutch 90 disengaged (button 70 pushed in) button 70 and driver 40 are rotationally locked together with the button 70, the driver 40 and the display member 60 still being axially coupled.

When dispensing a dose, the dose button 70 and clutch 90 are moved axially relative to the mechanism compressing the clutch spring 103. Because the proximal clicker part 102 is splined to the inner body 20 and the axial load passing through the clicker teeth 105, 106 locks the distal clicker part 101 in rotation to the proximal clicker part 102, the mechanism is forced to move axially whilst the dial sleeve 62 and number sleeve 61 are free to spin back into the outer housing 10. The interaction of mating threads between the piston rod 30, driver 40 and inner body 20 delivers a mechanical advantage of 2:1. In other words, axially advancing driver 40 causes the piston rod 30 to rotate which due to the threaded engagement of piston rod 30 with the inner body 20 advances the piston rod. During dose dispensing dispense clicker 68, 71 is active which involves button 70 and display member 60. The dispense clicker provides primarily audible feedback to the user that drug is being dispensed.

The end of this step is shown in FIG. 19. At this point the dose is complete and when the user removes the force from the end of the dose button 70, the clutch spring 103 pushes this dose button 70 rearwards, re-engaging the teeth 65 and 95 between the clutch and the dial sleeve.

Resetting the device starts with removal of the cartridge holder 80 and replacing an empty cartridge with a full cartridge 81. As the cartridge holder is re-attached, the bung of the new cartridge contacts bearing 31, thus pushing piston rod 30 back into the housing. Initially, the piston rod 30 screws into the inner body 20, thereby axially disengaging the coupler 43 from the proximal drive sleeve 42 against the biasing force of spring 103. Once disengaged the coupler 43 is free to start rotating together with distal drive sleeve 41 and continues to do so as the cartridge holder 80 is moved axially into engagement with the inner body 20.Thus, the distal drive sleeve 41 rotates with respect to the proximal drive sleeve 42 which is still rotationally constrained in inner body 20 as clicker parts 101 and 102 are pressed together by compressed spring 103. As the distal drive sleeve 41 rotates, last dose nut 50 is reset to its (distal) start position. Coupling the cartridge holder 80 to inner body 20 backs off the mechanism due to the bayonet structure 23 allowing re-engagement of the proximal drive sleeve 42 with coupler 43 and thus the distal drive sleeve 41.

In the following the cap or cap assembly 120 is described in more detail. An embodiment of the cap is shown in FIGS. 20 to 25.

The cap 120 has a distal end 121 and a proximal end 122. It serves to cover and protect the cartridge holder 80 from damage and the cartridge 81 itself from dust and dirt ingress on to the area around the septum. The cap 120 is designed to accommodate a distal part of the pen injector which is moved into the cap 120 through a proximal opening of the cap 120. The cap 120 may be attached to the remainder of the drug delivery device 1 in such a manner that the needle arrangement 180 attached to the cartridge or to the cartridge holder and the cartridge holder 80 are located inside the cap 120, in particular, when the cap is fixed to the remainder of the device. The cap 120 is detached before use of the drug delivery device 1, such as to set and/or dispense a dose of drug. The interior of the cap 120 is formed such that there is enough space for the needle arrangement 180 attached to the cartridge and the cartridge holder 80. The cap may be configured such that it covers the remainder of the device on all sides, when it is attached. The proximal opening of the cap may be the only opening of the cap. Means (not shown) for guiding and holding the cartridge holder 80 and the needle arrangement 180 may be provided on the inner surface of the cap 120.

FIG. 20 shows an exploded view of the cap 120 comprising an outer cap element 130 and an inner cap element 131. Furthermore, the clip element 134 is shown. The inner and outer cap elements and, preferably the clip element, form together a cap assembly 200, which is described later on in detail. The outer and inner cap elements 130, 131 are formed by or made by a metal sleeve and a plastic sleeve, respectively. The sleeves can be assembled together to form the removable cap 120. The outer and inner cap elements 130, 131 are connected by suitable means, e.g. adhesive means, positive locking, friction locking and/or a snap interaction. The clip element 134 allows connection of the injector pen 1 by means of the cap 120 to a shirt or jacket pocket and is always handy for that reason. An aperture 135 in the outer cap element 130 enables the clip element 134 to cooperate with, such as to snap to, the inner cap element 131.

The outer cap element 130 is preferably made of metal or of a metal alloy; the inner cap element 131 is preferably made of plastic. The combination of the metal outer cap element 130 and the plastic inner cap element 131 provides a high-quality look and pleasant touch. Also, the metal outer cap element 130 provides a hard wearing exterior surface of the device. The cap 120 is not too heavy and allows comfortable handling. The design of the inner component of the cap 120 allows retaining the clip element 134 and provides sufficient space to accommodate a standard needle and needle cover fitted to cartridge holder 80 inside the cap 120, in particular, when the cap is attached to the cartridge holder or another part of the device.

The outer cap element 130 may be a 0.4 to 0.6 mm thick aluminium element that provides a metal skin over the polymer inner cap element 131. The form of the cap 120 may be similar to that of a cap completely made of plastic. Such a cap 120 may substitute a cap completely made of plastic with no change in the tactile feel during attachment. Similar plastic features of the inner cap element 131 will not increase the risk of wear that may otherwise occur if attaching a plain metal sleeve to the existing plastic cartridge holder retention features.

The inner and outer cap elements 131, 130 are sleeve-shaped. The metal sleeve can be deep drawn from a metal sheet and then anodised over at least the outer surface. The anodising provides a high quality and hard wearing exterior surface to the cap 120 and enables the cap 120 to be given a variety of metallic colors. The removable cap 120 comprising the metal outer cap element 130 and the plastic inner cap element 131 can then be attached to a pen housing/mechanism which may be also made with a similar metal sleeve, to provide a reusable injection device that has a high quality visual appearance and a robust surface.

This design minimises cost and provides robust hard-wearing features. Hence the use of a combination of metal and plastic sleeve-shaped components enables the plastic sleeve to be moulded with features that attach to the plastic cartridge holder cap retention means. The cap retention means of the cartridge holder and/or of the cap assembly may be provided in the proximal section of the respective component.

FIG. 21 shows a sectional view of a proximal region of the outer cap element 130. FIG. 22 shows a three-dimensional cut-out view of this component. The outer cap element 130 is formed by a metal sleeve deep drawn with reduced thickness at the open end section. The very proximal region is rolled over to form a rounded or folded end 161. Such rolling back of the material may form a beading. In this embodiment the material of the outer cap element 130 has been bent once. Nevertheless, the material may be bent more than once. Such bending means that sharp edge 147 is on the inner surface of the outer cap element 130 and therefore is not accessible by the user.

Due to the thinner material of the open end, which is created during the deep drawn process, and then forming the beading, a circumferential recess 143 is formed on the inner surface of the outer cap element 130. This recess 143 serves as space into which the inner cap element 131 can deform when attaching the cap 120 to the cartridge holder 80. The sharp edge 147 is the proximal edge of the recess 143, the edge 147 serving to retain the plastic inner cap element 131 after assembly.

FIG. 23 shows a sectional view of a proximal section 141 of the cap 120 during attachment to the drug delivery device 1. During attachment the cap 120 including the inner and outer cap elements 131, 130 moves proximally with respect to the cartridge holder 80 in such a manner that the cartridge holder 80 moves into the cap 120.

The outer cap element 130 has a proximal section 141 comprising a cavity 143 on the inner surface of the outer cap element 130. The cavity 143 is formed as a circumferentially running recess in this embodiment. Alternatively the cavity 143 may have another form which may correspond with the form and size of the deformable region 151 of the inner cap element 131.

The thickness of the outer cap element 130 in the region of the cavity 143 is smaller than the thickness of a distal section or a middle section of the outer cap element 130. The distal edge 145 of the cavity 143 is formed in the shape of a ramp which allows a gentle transition between the middle section of the outer cap element 130 and the cavity 143 located in the proximal section 141. The proximal edge 147 of the cavity 143 is steeper than the distal edge 145 and may be formed as a sharp edge.

The inner cap element 131 comprises cap snap means 149 located on the inside of a proximal section of the inner cap element 131 and suitable for engaging with a cap retention means 155 located on the cartridge holder 80 of the drug delivery device 1. The cap snap means 149 is formed by at least a proximal part of the deformable region 151 that may be deformed during attachment and detachment in order to lock the cap snap means 149 to the cap retention means 155 of the drug delivery device 1 and to release the cap snap means 149 from the cap retention means 155. The cap snap feature 149 comprises a raised internal bump feature 153 or finger and a cavity 171 where the inner cap element 131 in the region of the cavity 171 is thinner than in other regions; the cavity 171 may be formed by the deformable region 151. The internal bump feature 153 has a proximal slope being less steep than a distal slope.

The reduced thickness of the inner cap element's cavity 171 enables the deformation of the cap snap means 149, thereby allowing engaging to the cap retention feature 155. Due to the cavity 143 of the outer cap element 130 there is a gap between the outer and inner cap elements 130, 131. The deformable region 151 is deformable into the cavity 143 of the outer cap element 130. In other words, the deformable region 151 is deformable into the gap between the outer and inner cap elements 130, 131.

According to one embodiment, the proximal end 173 of the cap snap means 149 extends proximally over the proximal edge 147 of the cavity 143; the proximal edge 147 preventing outwards movement of the proximal end 173 of the cap snap means 149 and to hold this end circular. According to a further embodiment, the proximal end 173 of the cap snap means 149 does not protrude over the edge 147. In particular, there may be no need for the proximal end 173 to protrude over the edge 147 as the clip holds both cap parts together axially.

The cap retention means 155 is located on the outer surface of the plastic cartridge holder 80. The cap retention means 155 comprises an elevation 157 which may have a base area formed as trapezium, circle, triangle or any other shape. In one embodiment two elevations 157 may be arranged on opposite sides of the cartridge holder 80, as shown in FIGS. 3 and 6. In one embodiment there are two or more than two elevations that are arranged equally or non-equally spaced on the drug delivery device 1.

The elevation 157 has proximal and distal slopes; the latter being less steep than the proximal slope of the elevation 157. The distal slope enables easy sliding of the proximal slope of the internal bump feature 153 over the top of the elevation 157 during attachment. The steeper slopes of both the elevation 157 and the internal bump feature 153 hinder distal movement of the internal bump feature 153 once it has moved over the top of the elevation 157, thereby preventing backward movement of the internal bump feature 153 after attachment. However, the application of a sufficient force by the user pulling the cap 120 distally pulls the internal bump feature 153 over the elevation 157 again, thereby allowing detachment of the cap 120. Since the distal slope of the internal bump feature 153 and the proximal slope of the elevation 157 are steeper, the force required for detachment is higher than for attachment, which prevents accidental detachment of the cap 120. Nevertheless, alternative internal bump feature 153 and elevation 157 embodiments may have other slope designs, which may be symmetrical.

When the internal bump feature 153 slides over the elevation 157, the internal bump feature 153 is pushed towards the outer cap element 130. Since the proximal end 173 of the cap snap means 149 is held in its position by the proximal edge 147 of the outer cap element 130, the resulting torque deforms the deformable region 151 outwardly and allows the nose tip to slide over the elevation 157. The cavity 143 of the outer cap element 130 allows space to accommodate at least some of the deformation of the plastic inner cap element 131 when the internal bump feature 153 slides over the elevation 157 during attachment of the cap 120.

FIG. 24 shows a sectional view of the proximal section of the cap 120 after attachment to the drug delivery device 1.

The internal bump feature 153 is engaged behind the proximal edge of the elevation 157. The elevation 157 engages to the cavity 171 of the inner cap element 131. Though the internal bump feature 153 has slid over the elevation 157, the cap snap feature 149 is still deformed into the cavity 143 of the outer cap element 130. The combination of the proximal edge 147 of the outer cap element 130 holding the proximal end 173 of the cap snap means 149 in its position and the elevation 157 pushing the deformable region 151 into the cavity 143 of the outer cap element 130 cause a close or interference fit of the cap snap feature 149 over the elevation 157, thereby holding the cap 120 in the attached position.

FIG. 25 shows a sectional view of the proximal section of another embodiment of cap 120 after attachment to the drug delivery device 1.

This embodiment differs from the one described above by the design of the inner cap element 131. The proximal end 173 of the cap snap means 149 does not extend over the proximal edge of the cavity 143, which allows a deformation in such a manner that the proximal edge 173 also moves into to the cavity 143 during attachment. In this embodiment the cap snap means 149 are able to deform more readily with less force input required from the elevation 157.

The features of the embodiments mentioned above may be combined. The layout, function, and number of components may be changed in other embodiments.

In the following, the clip element 134 is described in more detail with reference to FIGS. 26 to 39.

FIGS. 26 and 32 show the clip element 134 or fixing element of the drug delivery device 1. By means of the clip element 134, a fixation or attachment of a cap, e.g. the previously described cap 120 or a cap assembly 200 (see also below) of the drug delivery device 1 or the drug delivery device 1 may be fixed to a further component. The clip element 134 comprises a fixing portion 168 or main body with an elongate shape (see FIG. 31). Moreover, the clip element 134 comprises a slight curvature at a distal end (on the left in FIG. 26) of the clip element 134.

The clip element 134 comprises two components, i.e. a first component 300 and a second component 301 (see FIGS. 31 to 38, for example). Each one of the first and the second component 300, 301 is integrally formed. This may mean that the first and the second component 300, 301 are single-piece components. The first and the second component 300, 301 are attached, preferably non-releasably attached, to one another. The second component 301 is adapted and arranged to at least partly receive the first component 300. In particular, the first component 300 is at least partly introduced into the second component 301. Thus, the second component 301 may provide an outer shell of the clip element 134.

The first component 300 is at least in parts flexible and/or elastically deformable. In particular, the first component 300 comprises a flexible section. The flexible section provides a local radial flexibility of the first component 300 enabling the attachment of the clip element 134 to a further component, e.g. a jacket pocket. The first component 300 comprises plastic. In particular, the first component 300 is a plastic component. This may provide a certain degree of elastic deformability of the first component 300 per se. The first component 300 is injection moulded, for example.

In section, the first component 300 has an I-like shaped region (see, for example, FIG. 37). One horizontal stroke or bar of the “I” may, thereby, at least in parts be received by the second component 301 (upper horizontal stroke in FIG. 37). In the following, this stroke is referred to as “the upper horizontal stroke”. The upper horizontal stroke may constitute the previously mentioned main body or elongated body 168. A further horizontal stroke or bar of the “I” may be received by the previously mentioned cap 120, which is described later on in more detail. A vertical stroke or bar of the “I” may connect the two horizontal strokes.

The first component 300 comprises a tip 303 (see FIGS. 38 and 39, for example). The tip 303 is arranged in a proximal end section of the clip element 134. The tip 303 may constitute the very proximal region of the first component 300. In particular, the tip 303 may constitute the proximal end of the upper stroke of the “I”.

In the proximal end section, a thickness or radial extension of the first component 300 reduces towards its very proximal end. Accordingly, the tip 303 comprises a reduced thickness as compared to further sections of the first component 300, e.g. a distal section or a middle section. In other words, the tip 303 is thinner or has a reduced radial extension as compared to the remainder of the first component 300. On an upper side of the tip 303, i.e. that side, which faces the second component 301, the tip 303 may be slightly sloped. The thin tip 303 enables the first component 300 to flex locally in this region, as mentioned above.

The second component 301 may be made of a rigid material. In particular, the second component 301 may comprise a material which is more rigid than the material of the first component 300. The second component 301 may comprise or be made of metal or a metal alloy, e.g. steel or aluminium. The second component 301 may completely consist of metal. In this embodiment, the second component 301 may be stamped from a sheet of metal and then plated. In an alternative embodiment, the second component 301 may comprise fibreglass. The second component 301 may completely consist of fibreglass.

The second component 301 comprises an elongate shape having rounded edges. The second component 301 comprises a shape which is adjusted to the shape of an upper side of the first component 300 such that the second component can at least partly receive and/or cover the first component 300. The second component 301 comprises folded over edges or side walls. The folded over side walls may comprise a radial extension or height similar or equal to a thickness of one of the horizontal strokes of the previously described “I” (see FIG. 37). The second component 301 further comprises a curvature in a distal end section. By means of the rigid and hard material of the second component 301, a high quality and hard-wearing exterior surface of the clip element 134 is provided. In the embodiment where the second component 301 comprises metal, the second component 301 can further be given a variety of metallic colors.

The second component 301 further comprises a cavity or clearance region 304 (see FIG. 39). The cavity 304 is arranged on the underside of the second component 301, i.e. that side of the second component 301 which faces the first component 300 when the components 300, 301 are attached to one another. The cavity 304 is delimited by the folded over side walls. The design of the tip 303 allows it to flex into the cavity 304 of the second component 301, thus replicating a pinching effect of a standard pocket clip. In this way, a measure of retention is provided when the cap 120 and, hence, the device 1 is placed into a pocket or similar.

The first and second component 300, 301 are firmly connected to one another. Preferably, the first and the second component 300, 301 are non-releasably connected to one another. The second component 301 is press fitted to or clipped onto the first component 300. In particular, the second component 301 is press-fitted over the first component 300, thus providing a robust and hard-wearing shell for the first component 300.

The second component 301 comprises a retaining feature 302, which is shown in FIGS. 33, 36 and 37, for example. The retaining feature 302 may extend along the whole length of the second component 301. The retaining feature 302 may comprise the previously mentioned side walls of the second component 301. The fold over of the respective side wall is greater than 90 degrees with respect to a lateral axis of the clip element 134. The fold over may be 91, 92, 93, 94, 95, 100 or 105 degrees, for example. The folded over side walls do not contact an underside of the second component 301, wherein the underside may be that side of the second component 301 facing and/or receiving the first component 300 when the clip element 134 is assembled.

The folded over side walls of the second component 301 delimit an inner space of the second component in which the first component 300 is partly received when assembling the clip element 134. For coupling the first component 300 and the second component 301 to one another, in particular for clipping the second component 301 onto the first component 300, the first component 300 is partly or wholly introduced into the second component 301. An upper side of the first component 300 is received between the folded over side walls of the second component 301. In particular, the upper horizontal stroke of the “I”-shaped first component 300 is introduced over its whole length between the folded over side walls 302 of the second component 301. The folded over side walls of the second component 301 thereby keep the first component 300 in a predefined position with respect to the second component 301. The design of the components 300, 301 allows for an elastic deformation especially of the second component 301 when the first component 300 is inserted past the folded over side walls. The second component 301 forms a C-section when viewed in cross section (see FIGS. 36 and 37). This allows a relatively large amount of flexibility of the tips of the ,C′, when the second component 301 is clipped onto the first component 300. The first component 300 acts as a solid block in compression. Once inserted, the second component 301 may spring back for retention. Due to the fold over of the side walls being just greater than 90 degrees, the second component 301 is firmly retained once press-fitted over the first component 300.

However, before the second component 301 and the first component 300 are connected to one another as described above, the first component 300 of the clip element 134 is secured to the cap 120. For securing the clip element 134 and, in particular the first component 300, to the cap 120, the first component 300, comprises a guiding element 150, which can be seen from FIGS. 26 and 31, for example. The guiding element 150 is disposed in a distal end section of the first component 300 at an inside of the above mentioned curvature. The guiding element 150 is arranged on an underside of the first component 300 facing away from the second component 301. The guiding element 150 may constitute or comprise a rail such that the clip element 134 may be guided by an element receiving the guiding element 150, preferably, along a longitudinal axis of the clip element 134 or the device 1.

The guiding element 150 extends over less than half of the axial extension of the first component 300 of the clip element 134. The guiding element 150 comprises a T-shaped cross-section for facilitating the mentioned guiding functionality (see also FIG. 29). In order to form the T-shaped section, the guiding element 150 comprises a receiving portion 152 (see FIG. 26). The receiving portion 152 may constitute the horizontal stroke or bar of the “T” of the T-shaped section. Preferably, the receiving portion 152 is configured to be received by one or more openings or apertures of the components to which the clip element 134 is to be mounted, e.g. in a cap assembly 200 (see FIGS. 29 and 30).

Furthermore, the guiding element 150 comprises a guiding portion 158 (see FIG. 26). The guiding portion 158 constitutes the vertical stroke or bar of the “T” of the T-shaped section of the guiding element 150. The guiding portion 158 may be a web connecting the elongated main body (upper horizontal stroke of the “I”) of the first component 130 with the receiving portion 152. The guiding portion 158 may further be received by or arranged in one or more openings of the components to which the clip element 134 is to be mounted, e.g. in the mentioned cap assembly 200.

The clip element 134, particularly the guiding element 150, comprises a connection feature 154. The connection feature 154 comprises or constitutes a protrusion protruding radially at the underside of the first component 130. Preferably, the connection feature 154 is configured to interact with a corresponding connection feature 170, e.g. of an inner part or cap element 131 (see FIG. 28) for connecting the first component 300 and the cap 120. The connection feature 154 is disposed in a proximal end section of the guiding element 150. The connection feature 154 may further comprise or constitute a distal face of the guiding element 150. The connection feature may be designed to establish a snap fit connection to the inner cap element 131

The first component 300 further comprises a feature 156. The feature 156 comprises a radial face with a normal perpendicular to the longitudinal axis (not explicitly indicated) of the first component 300 and a longitudinal face which is designed to hide or cover over any gaps between the first component 300 of the clip element 134 and the outer part 130 resulting from tolerances in manufacture and assembly. The feature 156 is designed to be in small amount of clearance rather than abutting in nominal tolerance conditions. In particular, the feature 156 may be configured to be in small amount of clearance to one or more corresponding components to which the clip element 134 is to be mounted, e.g. in the cap assembly 200 (see FIG. 30).

Moreover, the clip element 134, in particular the first component 300, comprises an attachment feature 160. The attachment feature 160 may be configured to interact with a further component (see depression 166 in FIG. 27). The attachment feature 160 comprises a bump or pip. The attachment feature 160 is axially spaced from the guiding element 150 and arranged near a proximal end of the first component 300 and/or the clip element. The attachment feature is arranged on the underside of the first component 300 facing away from the second component 301. The attachment feature 160 is, preferably, configured to interact with the outer part 130 by means of mechanical contact, or close proximity to create a ‘pinch point’. Thereby, fixation or attachment of the cap assembly 200 or drug delivery device 1 to the further element, such as a shirt pocket of a user of the assembly 200 or the device 1 may be facilitated or aided. Particularly, said mechanical contact may increase the friction or the grip force and, therewith, the reliability of the attachment of the cap assembly 200 to the further element.

FIG. 27 shows a perspective view of an outer part or outer cap element 130 which may be or relate to the above-mentioned outer cap element. The outer part 130 comprises an elongate shape. The outer part 130 further comprises a sleeve-like shape. Preferably, the outer part 130 is made of a metal, e.g. from aluminium. To this effect, the outer part 130 is, preferably, formed or fabricated by deep drawing (as mentioned above). The outer part 130 further comprises the previously mentioned opening 164. The opening 164 is arranged at a distal end of the outer part 130. The opening 164 is, preferably, formed from the outer part 130 by punching. The outer part 130 may further comprise a proximal opening which is not explicitly indicated in FIG. 27.

Formed within the opening 164 is a corresponding guiding feature 162 corresponding to the guiding element 150 described by means of FIG. 26. The corresponding guiding feature 162 extends—originating from the opening 164—in a proximal direction of the outer part 130. The corresponding guiding feature 162 may be a guide slot. The corresponding guiding feature 162 may be configured to receive the guiding portion 158 of the guiding element 150 such that the guiding portion 158 is arranged inside the corresponding guiding feature 162. Preferably, the opening 164, the corresponding guiding feature 162 and the clip element 134 are configured such that the guiding element 150 can be introduced in or received by the opening 164. When, in particular after introduction of the guiding element 150 into the opening 164,—e.g. during an assembly of the cap assembly 200—the first component 300 is pushed proximally, the guiding portion 158 may be received by or arranged in the corresponding guiding feature 162, wherein the receiving portion 152 is, preferably, only received by the remainder of the opening 164 and arranged inside the outer part 130 and/or the inner part 131 (see FIGS. 29 and 30).

The outer part 130 further comprises the previously mentioned depression 166. The depression 166 receives or interacts with the above-mentioned attachment feature 160 of the clip element 134 when, e.g., the first component 300 and the outer part 130 are assembled (see FIGS. 29 and 30 below). Preferably, the attachment feature 160 extends into the depression 166 and/or contacts the outer part 130 in the depression 166. The depression 166 is axially, particularly proximally, spaced from the opening 164 along a longitudinal axis of the outer part 130. Preferably, the depression 166 is shaped according to the attachment feature 160, i.e. with similar curvature as the mentioned bump of the attachment feature 160 (see FIG. 26).

FIG. 28 shows a perspective top view of an inner part 131. The inner part 131 may be a sleeve and configured to be introduced in the outer part 130. The inner part 131 comprises a corresponding connection feature 170. The corresponding connection feature 170 corresponds to the connection feature 154 of the first component 300 such that the first component 300 can be connected to the inner part 131 by an interaction of the connection feature 154 and the corresponding connection feature 170 (see FIG. 30). The corresponding connection feature 170 may constitute or comprise a proximal face of the inner part 131. The inner part 131 further comprises an opening 172. The opening 172 is arranged at or near the distal end of the inner part 131. The opening 172 may further be shaped similar to the opening 164 of the outer part (see FIG. 27). Formed within the opening 172 is a corresponding guiding feature 172 a corresponding to the guiding element 150.

FIG. 29 shows a schematic section of parts of a cap assembly 200 (see also FIG. 30). The assembly 200 comprises the previously described clip element 134 and the outer part 130 and the inner part 131. FIG. 29 shows the mentioned components in an assembled state. An inner side of the cap assembly 200 is shown at the bottom and an outer part is shown at the top of the section shown in FIG. 29. In the depicted situation, the inner part 131 is arranged in the outer part 130 and at least a section of the clip element 134 and/or the guiding element 150 extends through the opening 164 of the outer part 130 and, preferably, also through the opening 172 of the inner part 131. To this effect, the openings 164 and 172 may overlap in the cap assembly 200. It is further shown in FIG. 29 that the guiding element 150 comprises the T-shaped section (said “T” is depicted upside down), as described above. The section of the whole first component 300 may, thereby, be shaped I-like, as described above. The guiding portion 158 is arranged in the corresponding guiding feature 162 (see also FIG. 29). The guiding element 150, particularly the receiving portion 152 may prevent an (outward) radial movement of the clip element 134 with respect to the outer part 130 and/or the inner part 131, for example. This is because the corresponding guiding feature 162 is too narrow, as to allow for the receiving portion 152 to radially pass or move through the corresponding guiding feature 162.

FIG. 30 shows a longitudinal section of parts of the cap assembly 200. The cap assembly 200 comprises a longitudinal axis X. The longitudinal axis X may coincide or be collinear with the longitudinal axis of the clip element 134, the outer part 130 and/or the inner part 131. Also, a drug delivery device in which the cap assembly 200 is attached is shown in FIG. 30 which shows, e.g. the cartridge holder 180.

The clip element 134 closes the opening 172 of the inner part 131 and the opening 164 of the outer part 130 such that a rounded shape of the cap assembly 200 results. The connection feature 154 is arranged at least partly in the opening 164 of the outer part 130, as well as in the opening 172 of the inner part 131 (openings are not explicitly indicated in FIG. 30). Particularly, the corresponding guiding feature 162 is configured to receive the receiving portion 152 of the guiding element 150 such that the receiving portion 152 is arranged inside of the outer part 130 and also inside the inner part 131.

The clip element 134, in particular its first component 300, and the inner part 131 are connected with one another. Particularly, the connection feature 154 interacts with, preferably abuts, the corresponding connection feature 170 via a snap interaction such that the clip element 134, in particular the first component 300, and the inner part 131 are connected with respect to one another. The clip element 134 and the inner part 131 are, preferably, reliably connected to one another, as the distal face of the connection feature 154 and the proximal face of the corresponding connection feature 170 abut. In order to connect the mentioned components or during the connection, at least one of the first component 300 and the inner part 131, may at least slightly be deformed. The connection feature 154 blocks proximal movement (i.e. to the right in FIG. 30) of the inner part 131 with respect to the outer part 130 such that the inner part 131 is retained within the outer part 130.

The previously mentioned feature 156 is - under nominal tolerance conditions - arranged in a small amount of clearance to a distal face of the inner part 131 and a distal face and a radial face of the outer part 130 (faces are not explicitly indicated). Although this is not explicitly indicated in FIG. 30, the attachment feature 160 of the clip element 134, preferably, mechanically contacts or lies in close proximity to the depression 166 of the outer part 130 (see description above).

Also further components e.g. of a drug delivery device, wherein the cap assembly 200 may be applied to, are shown. Such components relate to a cartridge or cartridge holder 180 which may retain a drug (not explicitly indicated). Furthermore, an injection needle 182 is shown which is in fluid communication with the drug from the cartridge or cartridge holder 180. It is shown that the inner part 131 accommodates the needle 182, an inner needle cover and furthermore at least a section of the cartridge or cartridge holder 180.

The inner part may, advantageously, be designed to be mouldable by an injection moulding process with simple open-shut injection mould tooling. Thereby, it can be manufactured by a low-cost moulding process.

It should be acknowledged that all of the concepts disclosed above and below can be combined especially as far as they concern concepts relating to a cap or cap assembly. Further, the present disclosure may sometimes address the same elements with different expressions which, of course, should not be understood as forming different elements merely because of the fact that they are addressed slightly differently herein. Specifically: The cap 120 (see FIG. 3) may be or relate to the cap assembly 200. The cartridge or cartridge holder 180 may be or relate to the cartridge 81 and/or to the cartridge holder 80. The metal element of the cap may be or relate to the outer part 130. The plastic element of the cap may be or relate to the inner part 131. The outer cap element may be or relate to the outer part 130. The inner cap element may be or relate to the outer part 131. The aperture 135 may be or relate to the opening 164. Also, elements not explicitly mentioned in the enumeration above may be addressed with different expressions.

It was discovered that, when assembling the cap assembly or cap as disclosed in the previous embodiments, it is difficult to secure components of the cap, for example the inner and the outer cap element 130, 131, with respect to each other reproducibly in a defined relative angular orientation.

In the following, an embodiment of a cap or a cap assembly is disclosed which addresses this issue in conjunction with FIGS. 40 to 43. Therein, the cap assembly as well as a method of assembling the cap assembly are described. The components of the cap assembly disclosed below can be the ones as disclosed further above. Accordingly, features disclosed herein below with respect to the cap assembly can also apply to the further caps or cap assemblies disclosed herein.

FIG. 40 shows components of the cap assembly in an unassembled state. As is apparent from FIG. 40, the components for the cap assembly comprise a first cap component, which is herein above and below also designated as inner cap element 131, and a second cap component, which is herein above and below also addressed as outer cap element 130. Further, the cap components for the cap assembly comprise a third cap component, which is herein above and below also referenced as clip element 134. The first and second cap components are formed sleeve-like, where the first cap component is adjusted to be received in and secured to the second cap component.

For the assembling of the cap assembly as illustrated in FIGS. 42A and 42B, for example the first cap component 131 can be arranged on a fixture and the second cap component 130, e.g. a deep-drawn metal component, is guided over the first cap component until a defined end position is reached.

As can be seen in FIG. 40, the first cap component 131, which is preferably an injection moulded plastic part, comprises a guide track 401, e.g. a groove. The guide track is axially oriented. The guide track is, preferably, arranged in a section of the first cap component 131, which is oriented axially. The guide track may run parallel or essentially parallel to the longitudinal axis X of the first cap component 131. Preferably, in the region with the axial guide track the cap component 131 does not or not significantly widen in the radial direction along the axis X. In a different region of the cap component, e.g. a region 402 which axially overlaps with the region comprising the guide track and/or a non-overlapping region, the cap component, particular the exterior surface, may widen more in the radial direction as seen along the axis X than in the region with the guide track 401.

The guide track 401 is preferably provided in a region which is spaced from a distal end and/or from a proximal end of the first cap component 131. That is to say the start and/or the end of the track may be arranged at a distance from the proximal end and/or from the distal end of the cap.

The guide track 401 may be offset in the proximal direction with respect to the opening 172 and/or the guiding feature 172 a which is provided at or near the distal end of the cap component. The guiding feature 172 a is intended for interaction with the third cap component, that is to say the clip element 134, as disclosed further above. The guide track 401 may also be distally offset from a proximal opening of the first cap component 131. The guide track and the guiding feature 172 a may be aligned with respect to each other. They may extend in a common plane. Preferably, the guide track 401 extends in the, preferably axial, direction predetermined by the guiding feature 172 a. As also disclosed further above, the third cap component 134 may be designed to be fixed to the first cap component by means of a snap-fit interaction provided between the third cap component and the first cap component 131, for example.

The second cap component comprises a guide feature 403 (best seen in FIG. 42 A). The guide feature 403 is formed by a protrusion protruding from an inner surface of the second cap component. The guide feature is arranged to interact with the guide track to form a guiding interface. The second cap component 130 further comprises the guiding feature 162 which has already been discussed further above. The guiding feature continues opening 164 in the proximal direction. The guiding feature 162 is axially oriented. It is expediently oriented in the same direction and or arranged at a corresponding angular position as the guide track 401 and/or the guiding feature 172 a, when the two cap components 130 and 131 have been assembled to each other.

The second cap component further comprises the depression 166 as disclosed further above. The second cap component is preferably manufactured by deep drawing. By means of a pressing operation that occurs as part of a multi-stage deep drawing process, the depression 166 may be formed and in the region of the depression 166, on the interior surface of the second cap component, the protrusion forming the guide feature 403 may be formed. The protrusion expediently has the complimentary shape of the depression, e.g. both may be of hemispherical shape. Thus, guide feature 403 may have a curved surface which is designed to interact with a bearing surface or bearing surfaces of the guide track 401, e.g. side walls of a groove. When the third cap component 134 has been connected to the first cap component 131, a bump or a pip 404 of the third cap component may be arranged within the depression 166 (see FIG. 43).

The guiding feature 172 a may form the fixing guide track, which guides the fixing feature of the third cap component 134, for example the connection feature 154 shown in FIG. 26, to the appropriate fixing feature provided in the interior of the first cap component 131. When the third cap component 134 has been fixed to the first cap component 131, the second cap component 130 may be secured relative to the remaining two components of the cap.

The first and second cap components 131, 130 are expediently adjusted with respect to one another such that their cross sections ensure that they can only be assembled to one another when they have a certain relative angular position or orientation. Accordingly, by way of the cross sections, at least a certain kind of pre-alignment may be provided. The pre-alignment expediently ensures at least that the guide feature 403 and the guide track 401 can be brought into cooperation. For example, the outer cross section of the first cap component and the inner cross section of the second cap component may be adjusted in their shapes to suit or match one another such that they can only be assembled or moved axially relative to one another when they have the correct orientation. The cross sections are, for this purpose, expediently not circular but rather designed to form a rotationally constrained interface between the two cap components. Therefore, it is expedient, to match the outer surface of a cross section of a region 404 of the first cap component to the inner surface of a cross section of a region 405 of the second cap component. The regions 404 and 405 may be arranged such that the surfaces do cooperate, e.g. to form the rotationally constrained interface, during the assembling process, before the guiding interface is established. For example, the region 405 may be arranged proximally offset from the guide feature 403 and the region 404 may be arranged distally offset from the distal end of the guide track 401.

The guide track 401 may, for example in its distal end region 406, comprise a lead-in region, where it accepts the guide feature 403 even if it is slightly misoriented. In the further course of the guide track, the guide feature 403 may be guided more tightly as compared to the lead-in region. The guide track may comprise an end stop 407, which is designed to abut the guide feature 403. The end stop may define an axial end position during the assembling process. In the region of the end stop 407, the guide track may comprise a curved surface, where the curvature, preferably, matches the one of the guide feature. This facilitates provision of a large area bearing surface between the two cap components in the end position.

The guide track 401 may extend in the axial direction over a length which is greater than or equal to one of the following values: 0.25*L, 0.3*L, 0.35*L, 0.4*L, 0.5*L, 0.55*L. Alternatively or additionally, the guide track 401 may extend in the axial direction over a length which is less than or equal to one of the following values: 0.8*L, 0.7*L, 0.6*L. “L” is the length of the first cap component, the second cap component or of the cap or cap assembly. The guide feature 403 may extend in the axial direction over a length which is less than the axial extension of the guide track, particularly less than a quarter of the axial extension of the guide track 401.

The guide feature 403 may protrude from a main body of the respective cap component by 0.5 mm or more, preferably by 1 mm or more.

The guide feature may be arranged at a distance from the proximal opening of the cap or the second cap component. This distance is preferably greater than the distance of the proximal end of the guiding feature 172 a or 162 from the distal end of the first or second cap component, respectively.

In order to assemble the cap assembly, the first cap component 131 and the second cap component 130 are arranged such that the guide feature 403 and the guide track 401 are brought into a mechanical cooperation. Preferably, for doing so, at first the surfaces of the cap components in regions 405 and 404 interact to ensure pre-alignment of the guide feature 403 and the guide track 401.This ensures preferably at least that the guide feature 403 can cooperate with the lead-in region of the guide track 401. Alternatively, a lead-in region might not be required if the pre-alignment is accurate enough to ensure that the guide feature 403 always engages the guide tack 401. Once the lead-in region has been passed, the axial movement between the first and the second cap component is tightly guided axially by the axial guiding interface which is then formed by the guide feature and the guide track such that relative rotation between the two cap components is prevented. Accordingly, it can be assured that the guiding feature 162 does guide the connection feature 154 of the third cap component appropriately to the corresponding fixing feature provided on an interior of the first cap component 131, such that the features can interact to connect the first and third cap components. This ensures that the cap is reliably assembled. Without this interface a significant relative rotation would still be possible, such that the fixing features of the first and third cap components could not interact reliably as explained in the introductory section. The tighter axial guiding via the guiding interface ensures that the cap components do have a defined relative position. A situation which is just before the assembling process has been finished is shown in FIG. 42 A on account of a partial sectional view and in FIG. 42 B based on a side view. The second cap component has almost reached its end position with respect to the first cap component. In the end position, the guiding interface is preferably still active. Expediently, the guide feature 403 may interact with the end stop 407 in order to indicate that the end position has been reached.

In FIG. 43 it is immediately apparent how the bump or pip 404 of the clip element rests in the depression 166, which simultaneously defines the guide feature 403 in the interior. The curved surface(s) of the guide feature have the advantage that the guide feature can, on its curved surface, take up some manufacturing tolerances, as along the radial extension of the curved surface there are different points where the guide feature could interact with a guide track.

It should be readily acknowledged that the guide track could also be provided on the second cap component and the guide feature could be provided on the first cap component. However, it is preferred that the guide track is provided on the first cap component and the guide feature on the second cap component, because by using the hemispherical depression as defining the hemispherical guide feature, the aesthetic appearance of the cap is not negatively affected as it might be, if a ridge were formed on the exterior surface to define a groove as guide track on the interior surface of the cap component.

The proposed design of the second cap component (which later forms the outer shell of the cap or cap assembly) enables the second cap component to be made of metal or a metal based alloy on a single press designed for deep drawing, without the requirement for any secondary forming operations to be added to the component after deep drawing. This minimizes cost and maximizes the output from the process, enabling a low cost drug delivery device to be assembled without sacrificing the aesthetic and perceived quality. Further, on account of the guiding interface which is formed a defined angular orientation of the cap components can be ensured.

The scope of protection is not limited to the examples given herein above. The disclosed subject matter is embodied in each novel characteristic and each combination of characteristics, which particularly includes every combination of any features which are stated in the claims, even if this feature or this combination of features is not explicitly stated in the claims or in the examples.

LIST OF REFERENCES CHARACTERS

1 drug delivery device

10 outer housing part

11 distal part

12 rotational hard stop/stop features/second rotational stop

13 aperture

20 inner body/housing

21 external thread

22 splines

23 bayonet features

24 window retention nose/retaining means

25 stop faces/first rotational stop

30 piston rod

31 bearing

32 external thread/first outer thread

33 external thread/second outer thread

40 driver

41 distal driver part/separate components/distal portion/first component

42 proximal driver part/separate components/proximal portion/second component

43 coupler

44 external thread/helical groove

45 stop faces

46 splines

47 teeth features

48 fingers/flexible arms

49 bearing surface

50 dose nut

51 stop faces

52 external ribs

53 internal thread

60 display member

61 number sleeve/first component

62 dial sleeve/other component

63 stop face

64 helical drive face/protruding thread

65 clutch features/teeth

66 bearing face/flange/contact features

67 opposite faces

68 ratchet arm/dispense clicker/clicker feature

70 button

71 ratchet teeth/dispense clicker/clicker teeth

72 end face

73 arms/fingers

74 snap features

80 cartridge holder

81 cartridge

82 bayonet connection

83 aperture

84 distal end

90 clutch

91 drive sleeve splines

92 clutch biasing teeth

93 snap apertures/snap features

94 splines

95 clutch teeth

100 clicker

101 distal clicker part/second toothed element

102 proximal clicker part/first toothed element

103 spring

104 splines

105, 106 clicker teeth

107 external splines

108 shaped splines

109 clutch biasing teeth

110 spring

120 cap

230 window

101 distal clicker part

102 proximal clicker part

130 outer part/metal element of cap/outer cap element

131 inner part/plastic element of cap/inner cap element

132 metal element of outer housing part

133 plastic element of outer housing part

134 fixing element/clip element

135 aperture of cap

136 aperture of outer housing part

137 end face (of cap)

141 proximal section

143 cavity

147 edge

149 cap snap means

151 deformable region

153 internal bump feature

155 cap retention feature

157 elevation

161 folded end

171 cavity

173 proximal end

150 guiding element

152 receiving portion

154 connection feature

156 feature

158 guiding portion

160 attachment feature

162 corresponding guiding feature

164 opening (outer part)

168 fixing portion

166 depression

170 corresponding connection feature

172 opening (inner part)

172 a guiding feature

180 cartridge/cartridge holder

182 injection needle

200 cap assembly

300 first component

301 second component

302 retaining feature

303 tip

304 cavity/clearance region

401 guide track

402 region

403 guide feature

404 region

405 region

406 distal end region

X longitudinal axis 

1. A multi-part cap assembly for a drug delivery device, comprising: a first cap component; and a second cap component, wherein the first cap component is assembled to the second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented.
 2. The cap assembly of claim 1, wherein the first cap component and the second cap component are configured such that, aside from the guiding interface, the relative angular orientations of the first cap component and the second cap component, in which the first cap component can be assembled to the second cap component are limited, wherein the relative angular orientations in which the first cap component and the second cap component can be assembled to one another are limited to a range of orientation angles, and wherein the axial guiding interface is configured to restrict the relative rotational movement to a restricted range of angles where the restricted range of angles is a subset of the range of orientation angles.
 3. The cap assembly of claim 1, wherein the cap assembly comprises a third cap component that is fixed to the first cap component by means of a first cap component fixing feature provided on the first cap component, which is designed and arranged to cooperate with a third cap component fixing feature provided on the third cap component in order to fix the third cap component to the first cap component, and wherein the second cap component comprises a fixing guide track that is arranged to guide movement of the third cap component fixing feature to the first cap component fixing feature.
 4. The cap assembly of claim 2, wherein the cap assembly comprises a third cap component that is fixed to the first cap component by means of a first cap component fixing feature provided on the first cap component, which is designed and arranged to cooperate with a third cap component fixing feature provided on the third cap component in order to fix the third cap component to the first cap component, wherein the second cap component comprises a fixing guide track that is arranged to guide movement of the third cap component fixing feature to the first cap component fixing feature, and wherein the third cap component fixing feature and the first cap component fixing feature are arranged to cooperate when they are arranged in a fixing range of relative angular orientations, wherein the fixing range does fully cover the relative angular orientations in the restricted range of angles but does not fully cover the relative angular orientations in the range of orientation angles.
 5. The cap assembly of claim 3, wherein the fixing guide track and the guide track extend in a common plane.
 6. The cap assembly of claim 3, wherein the first cap component is a sleeve-like component, the second cap component is a sleeve-like component, and the third cap component is a clip element, and the second cap component forms an outer surface of the cap assembly.
 7. The cap assembly of claim 1, wherein the second cap component is made of a metal or of a metal alloy and is a deep drawn component.
 8. The cap assembly of claim 1, wherein the guide track is provided on the first cap component and the guide feature is provided on the second cap component, and wherein the guide feature is formed by a protrusion provided on an inner surface of the second cap component.
 9. The cap assembly of claim 8, wherein an outer surface of the second cap component comprises a depression, where the protrusion is defined by the depression.
 10. The cap assembly of claim 9, wherein the cap assembly comprises a third cap component that is fixed to the first cap component by means of a first cap component fixing feature provided on the first cap component, which is designed and arranged to cooperate with a third cap component fixing feature provided on the third cap component in order to fix the third cap component to the first cap component, wherein the second cap component comprises a fixing guide track that is arranged to guide movement of the third cap component fixing feature to the first cap component fixing feature, and wherein a section of the third cap component is arranged in the depression.
 11. The cap assembly of claim 1, wherein the guide feature comprises one or more curved surfaces that are designed to interact with the guide track.
 12. The cap assembly of claim 1, wherein the guide track is an axial guide track that extends in the axial direction.
 13. The cap assembly of claim 1, wherein the first cap component and the second cap component are secured to each other such that relative rotational and axial movement is prevented.
 14. The cap assembly of claim 1, wherein the guide track is provided on the first cap component and the guide feature is provided on the second cap component, and wherein the guide feature is formed by a protrusion provided on an inner surface of the second cap component, and wherein an outer surface of the second cap component comprises a depression, where the protrusion is defined by the depression.
 15. A drug delivery device comprising the cap assembly of claim 1 and a cartridge contaning a plurality of doses of a drug, wherein the drug delivery device is configured such that the cartridge is replaceable.
 16. A kit for assembling a multi-part cap for a drug delivery device, comprising: a first cap component and a second cap component, which can be assembled for a cap assembly, wherein the first cap component can be received in and secured relative to the second cap component, and wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented.
 17. A method for assembling a multi-part cap for a drug delivery device, comprising the steps of: providing a first cap component; providing a second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented, introducing the first cap component into the second cap component such that the axial guiding interface is established, moving the first cap component and the second cap component relative to one another in the axial direction towards an end position, this movement being guided by the axial guiding interface, and securing the first cap component and the second cap component to one another in the end position.
 18. The cap assembly of claim 14, wherein the cap assembly comprises a third cap component and a section of the third cap component is arranged in the depression. 